_STACK SEGMENT STACK            ;8088宏汇编程序
    DW   64 DUP (?)             ;定义堆栈段
_STACK ENDS 
CODE    SEGMENT                 ;定义代码段
ASSUME CS:CODE,SS:_STACK

START: MOV  CX,0004H
       MOV  DI,3500H
       MOV  DX,[DI]
A1:    MOV  AX,DX
       AND  AX,0FH
       CMP  AL,0AH
       JC   A2
       ADD  AL,07H
A2:    ADD  AL,30H
       MOV  [DI+0AH],AL
       INC  DI
       PUSH CX
       MOV  CL,04H
       SHR  DX,CL
       POP  CX
       LOOP A1
A3:    JMP  A3
CODE   ENDS
    END     START
